Phantom CEL

Rico567

Top Post Dawg
Joined
Jun 13, 2003
Location
Central IL
TDI
2013 Passat TDI SEL Premium (Turned in 7/7/18)
Drove from the Midwest to VA last Monday & Tuesday. Got about 150 miles and stopped at a rest area, when I started off I had a CEL, no other symptoms. The Passat continued to run fine, and the manual was...not helpful. Checked the fluids that night at a motel in E Ohio, CEL still on the next day, stayed on all the way to Eastern VA. Passat then sat for three days, then I decided to go to a local Auto Zone and use their OBD reader to attempt to get code(s). Started car = no CEL. Car continues to run like a top, normal mpg, fluids fine.
Anyone else experience this temporary CEL?
 

Ol'Rattler

Top Post Dawg
Joined
Jul 3, 2007
Location
PNA
TDI
2006 BRM Jetta
It the problem is intermittent, some DTC's (Faults)
will turn on the light and will turn off the light if the problem is not currently active. Even though the faults is intermittent, you should be able to retrieve the DTC with VCDS even if the light goes off.

Almost forgot. AutoZone code readers are a waste of time on a Dub. What you need is VCDS.

Almost forgot 2. Do not go to AutoZone unless you hate your car and do't mind putting Chinese prone to fail parts in it.
 
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Rico567

Top Post Dawg
Joined
Jun 13, 2003
Location
Central IL
TDI
2013 Passat TDI SEL Premium (Turned in 7/7/18)
It the problem is intermittent, some DTC's (Faults)
will turn on the light and will turn off the light if the problem is not currently active. Even though the faults is intermittent, you should be able to retrieve the DTC with VCDS even if the light goes off.

Almost forgot. AutoZone code readers are a waste of time on a Dub. What you need is VCDS.

Almost forgot 2. Do not go to AutoZone unless you hate your car and do't mind putting Chinese prone to fail parts in it.
Thanks- I've got VCDS, it just happens to be on loan to our son at present. I'll run a check on the car as soon as I get it back.
And, no, I wouldn't buy parts at AZ, I usually just use them to dump waste oil.
 

VeeDubTDI

Wanderluster, Traveler, TDIClub Enthusiast
Joined
Jul 2, 2000
Location
Springfield, VA
TDI
‘18 Tesla Model 3D+, ‘14 Cadillac ELR, ‘13 Fiat 500e
Drove from the Midwest to VA last Monday & Tuesday. Got about 150 miles and stopped at a rest area, when I started off I had a CEL, no other symptoms. The Passat continued to run fine, and the manual was...not helpful. Checked the fluids that night at a motel in E Ohio, CEL still on the next day, stayed on all the way to Eastern VA. Passat then sat for three days, then I decided to go to a local Auto Zone and use their OBD reader to attempt to get code(s). Started car = no CEL. Car continues to run like a top, normal mpg, fluids fine.
Anyone else experience this temporary CEL?
Our experience with an intermittent CEL ended up being the DEF heater/temp sensor circuit. I don't remember which, specifically. The CEL was sporadic for several months before finally remaining on constantly. VW replaced the defective part for free under the extended DEF heater module warranty.
 

740GLE

Top Post Dawg
Joined
Aug 19, 2009
Location
NH
TDI
2015 Passat SEL, 2017 Alltrack SE; BB 2010 Sedan Man; 2012 Passat,
Thought the warring signs for that was "low DEF level refill or car wont start in 1200 miles"

Either way Autozone free code reader is as good for what you pay, ;) it was able to deduce my stuck exhaust flap on the jetta a few years ago.
 

VeeDubTDI

Wanderluster, Traveler, TDIClub Enthusiast
Joined
Jul 2, 2000
Location
Springfield, VA
TDI
‘18 Tesla Model 3D+, ‘14 Cadillac ELR, ‘13 Fiat 500e
Thought the warring signs for that was "low DEF level refill or car wont start in 1200 miles"

Either way Autozone free code reader is as good for what you pay, ;) it was able to deduce my stuck exhaust flap on the jetta a few years ago.
That message is for low exhaust fluid level. The check engine light and codes that I'm referring to are for a bad heater circuit or a bad temperature sensor.
 

Rico567

Top Post Dawg
Joined
Jun 13, 2003
Location
Central IL
TDI
2013 Passat TDI SEL Premium (Turned in 7/7/18)
Our experience with an intermittent CEL ended up being the DEF heater/temp sensor circuit. I don't remember which, specifically. The CEL was sporadic for several months before finally remaining on constantly. VW replaced the defective part for free under the extended DEF heater module warranty.
Thanks for the tip— given the number of the DEF heaters that appear to be failing, this is good to know. I have an appointment at 1000 tomorrow morning to get the heater core replaced under warranty (after a trip back from the east coast with a few chilly spots on the passenger side, but not too bad), and if I thought they wouldn't charge me for a diagnostic, I might try to get them to see if that CEL was caused by the DEF heater. But that's not likely to happen, so I'll just wait until I get my VCDS back.
 

jdyno718

Veteran Member
Joined
Sep 23, 2015
Location
Colorado
TDI
2012 VW Passat SE Manual
I got money that VeeDub is spot on with the DEF heater/temp sensor. I had the same intermittent CEL, went to Auto Zone to pull code, P203B, then used Google to determine it was DEF. Got it replaced under extended warranty.
 

Oilcan Boyd

New member
Joined
Dec 12, 2017
Location
Florida
TDI
2009 Jetta & 2014 Passat
I have a 2014 Passat with 129,000 miles. I just got the P203B fault code. I am trying to figure out if it is the AdBlue heater that went out or if it is the control module. Any help would be greatly appreciated.
 
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